Neuroscience
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Retracted Publication
Sustained hypoxia reduces GABAergic modulation on NTS neurons sending projections to ventral medulla of rats.
Peripheral chemoreflex is activated during short-term sustained hypoxia (SH), and the first synapse of these afferents is located in Nucleus Tractus Solitarius(NTS). NTS neurons projecting to the ventral lateral medulla (NTS-VLM) are part of the respiratory pathways of the chemoreflex. SH increases the magnitude of basal respiratory parameters in rats from Wistar-Hannover strain. ⋯ The data are showing that: (a) the amplitude of evoked inhibitory currents in NTS-VLM neurons of SH rats was reduced and not accompanied by any change in rise-time and decay-time; (b) the 1/CV2 and the number of failures in response to evoked currents were also affected by SH; (c) the frequency of spontaneous inhibitory currents was reduced by SH without changes in amplitude and half-width. These effects of SH were observed in NTS-VLM neurons located in caudal and intermediate NTS, but not in NTS-VLM neurons located in the rostral NTS. We conclude that SH causes a reduction in inhibitory modulation onto NTS-VLM neurons by pre-synaptic mechanisms, which may contribute to the observed changes in the respiratory pattern of Wistar-Hannover rats submitted to SH.
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Review Retraction Of Publication
TEMPORARY REMOVAL: GABAB Receptor-modulation of Thalamocortical Dynamics and Synaptic Plasticity.
GABAB-receptors (GABAB-Rs) are metabotropic, G protein-coupled receptors for the neurotransmitter GABA. Their activation induces slow inhibitory control of the neuronal excitability mediated by pre- and postsynaptic inhibition. Presynaptically GABAB-Rs reduce GABA and glutamate release inhibiting presynaptic Ca2+ channels in both inhibitory and excitatory synapses while postsynaptic GABAB-Rs induce robust slow hyperpolarization by the activation of K+ channels. ⋯ In the cerebral cortex, GABAB-Rs also modulate the most prominent emergent oscillatory activity-slow oscillations-as well as faster oscillations like gamma frequency. Further, recent studies evaluating the complexity expressed by the cortical network, a parameter associated with consciousness levels, have found that GABAB-Rs enhance this complexity, while their blockade decreases it. This review summarizes the current results on how the activation of GABAB-Rs affects the interchange of information between brain areas by controlling rhythmicity as well as synaptic plasticity.
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Retraction Of Publication
WITHDRAWN: Auditory Surprise Model Based on Pattern Retrieval from the Past Observation.
This article has been withdrawn: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been withdrawn at the request of the authors. The authors regrets that the reason for withdrawal is due to an disagreement in authorship and in scope of data disclosure. The authors apologize to the readers for this unfortunate error.